TY - JOUR ID - Haraoka2024 LB - Haraoka2024 AU - Haraoka, Yoshishige TI - Asymptotic analysis for confluent hypergeometric function in two variables given by double integral ST - Asymptotic analysis for confluent hypergeometric function in two variables given by double integral JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2024 VL - 44 IS - 4 SP - 505 EP - 541 DO - https://doi.org/10.7494/OpMath.2024.44.4.505 UR - https://doi.org/10.7494/OpMath.2024.44.4.505 AB - We study an integrable connection with irregular singularities along a normally crossing divisor. The connection is obtained from an integrable connection of regular singular type by a confluence, and has irregular singularities along \(x=\infty\) and \(y=\infty\). Solutions are expressed by a double integral of Euler type with resonances among the exponents in the integrand. We specify twisted cycles that give main asymptotic behaviors in sectorial domains around \((\infty,\infty)\). Then we obtain linear relations among the twisted cycles, and get an explicit expression of the Stokes multiplier. The methods to derive the asymptotic behaviors for double integrals and to get linear relations among twisted cycles in resonant case, which we developed in this paper, seem to be new. KW - strong asymptotic expansion KW - Stokes phenomenon KW - middle convolution KW - twisted homology SN - 1232-9274 ER -